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ARTICLE

Genesis of the Taolin Pb-Zn deposit in northeastern Hunan Province, South China: constraints from trace elements and oxygen-sulfur-lead isotopes of the hydrothermal minerals Deshui Yu 1,2 & Deru Xu 3

&

Zhaoxia Zhao 1,2 & Qinyi Huang 1,2 & Zhilin Wang 4 & Teng Deng 3 & Shaohao Zou 3

Received: 28 November 2019 / Accepted: 1 December 2019 # Springer-Verlag GmbH Germany, part of Springer Nature 2019

Abstract Located in the northeastern Hunan Province of South China, the Taolin Pb-Zn deposit is one of many metallic deposits structurally controlled by extensional faults in the central segment of the Jiangnan Orogen. The deposit occurs in a tectonic breccia zone between the Mufushan pluton and the Neoproterozoic Lengjiaxi Group. Field and microscopic observations reveal that the hydrothermal ore-forming processes at Taolin can be divided into five stages, from early to late: (1) coarse-grained quartz, (2) quartz + fluorite + chlorite + claybank sphalerite (Sp1) + galena + chalcopyrite, (3) quartz + barite + pale-yellow sphalerite (Sp2) + galena + chalcopyrite, (4) quartz ± chalcopyrite, and (5) fine-grained quartz, in which the stages 2 and 3 are regarded as the main Pb-Zn-forming events. LA-ICP-MS analyses show that Sp1 has higher contents of Fe, Mn, Co, In, and Sn, but lower contents of Ge and Sb, relative to the Sp2. Trace element concentrations of the sphalerite suggest a medium-low temperature hydrothermal event dominated in the Taolin deposit and that the ore fluids gradually decreased in the estimated average temperature and became relatively oxidized from stages 2 to 3. The δ18O values of ore fluids calculated from in situ analysis on the stages 2 and 3 quartz suggest the ore fluids are from a mixture of magmatic and meteoric waters. The δ34S values of sulfides/sulfates from stages 2 and 3 mineralization indicate a dominating magmatic affinity for sulfur. Further, lead isotope compositions for the stages 2 and 3 sulfides are similar to those of the Mufushan pluton, indicating that the ore metals may have been derived from the latter. We thus propose that the Taolin deposit precipitated from a medium-low temperature magmatichydrothermal system most likely related to the Mufushan pluton. Keywords Hydrothermal minerals . In situ analysis . O-S-Pb isotopes . Taolin Pb-Zn deposit . Northeastern Hunan Province of South China

Editorial handling: B. Lehmann Electronic supplementary material The online version of this article (https://doi.org/10.1007/s00126-019-00947-8) contains supplementary material, which is available to authorized users. * Deru Xu [email protected] 1

CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China

2

University of Chinese Academy of Sciences, Beijing 100049, China

3

State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, China

4

School of Geosciences and Info-Physics, Central South University, Changsha 410083, China

Introduction Vein-ty